The objective is to create a unique center-without-walls for the investigation of the diagnosis, etiology, mechanisms, treatment, and prevention of Huntington's Disease. A National Huntington's Disease Resource of 200 H.D. patients, 200 spouses, and 600 at-risk family members will be carefully ascertained and assessed for the longitudinal study of the epidemiology, genetics, pharmacology, neurophysiology of the disease by intramural and extramural investigations. A Center administration will maximize use of patients, personnel and equipment, will provide ethical guidelines and organize a program of education for medical students, residents, nurses and social workers, patients and families. Included in the educational program will be explanations of the research projects in this Center and elsewhere to ensure active participation and informed consent of the patient populations. Basic research studies in fibroblasts, neuroreceptors and animal models of H. D. will be conducted.